1. Field of the Invention
This invention relates to a fulling machine for textile materials in continuous rope or hose form, said machine being adapted not only to effect fulling operations, but also the washing of textile materials.
Inasmuch as the invention is mainly described by the component parts of the machine which effect fulling, reference will be to fulling machines exclusively, even though it is understood that the invention can be embodied to carry out combined or separate fulling and washing runs.
2. Description of the Prior Art
It is known that the fulling operation is intended for compacting the textile materials, that is, to induce a shortening of the piece length and a shrinkage of the fabric width. In the present patent, the lengthwise fulling operation will be principally dealt with.
Is is necessary, moreover, to establish that the term "textile material in continuous rope form" is used herein to connote a fabric piece having a certain length, the starting and the ending edge whereof are sewn together and united to form an endless annular band which is twisted like a rope (also called a strand). The rope form is thus distinguished from the form that an extended fabric piece usually has. The term "textile material in hose form" is used herein to distinguish a fabric piece having a certain length which is united, at the outset, by sewing it along its side edges or selvedges to form a hose-like structure, an annular rope being then formed as in the case referred to above. It is apparent that the processing in the hose form is more cumbersome and expensive than that in continuous rope form since it requires a supplementary sewing step along the full length of the fabric piece.
In the rope or hose fulling mills, only a single rope or hose of textile material should be processed, but it is customary, for economical reasons, simultaneously and in parallel to process a number of endless ropes which are appropriately held separate from each other.
A conventional fulling machine is composed of a large tub having an at least partially sloping bottom wall. The principal component parts which are installed in said tub to carry out the fulling operations are as follows: two superimposed rollers which are driven to rotation about their respective axes at the same surface speed, the endless fabric bands or ropes being intended to pass therebetween, the presser roller being pressed against the dragger rollers, at least a fulling channel which tapers from the intake end to the exit end, and wherein the fabric undergoes the fulling step (compacting) in the longitudinal direction, a basin which contains the fulling liquor (usually soap suds) by which the fabric is soaked prior to being passed between the two rollers aforesaid, and a partitioning and guiding frame to keep the fabric ropes separate from each other. Members for the open-width fulling are additionally provided, and these are usually composed by a couple of jaws and like members placed immediately upstream of said superimposed paired rollers. The latter members are both of no immediate interest to the ends of the present invention so that no reference thereto will be made hereinafter.
The fabric bands coming from the tub bottom are passed through the partitioning and guiding frame, are imbided with the fulling liquor, are passed between the superimposed and driven rollers and are fed forward thereby into and through the fulling channel to be compacted and are then arranged in laps on the sloping bottom wall of the tub to be fed back to the partitioning and guiding frame again.
The motive members which cause the continuous run of the endless fabric bands in the tub are thus only the superimposed rollers which also fulfil the task of urging the fabric through the fulling channel. The result is that the presser roller must be urged against the dragger roller with such a force as to overcome the drag of the fulling channel, because, otherwise, a slippage of the fabric would be originated between the two rollers and this might be conducive to scars and tears in the fabric.
Too high a pressure between the two rollers may cause serious damages to the fabric, especially if the fabric is in the rope form, and such damages appear in the form of the so called marblings or creases which sometimes cannot be removed. When operating in the hose form, conversely, it is possible to redress this shortcoming at least partially: in such a case, however, the increase cost for such a processing run must be taken over, as outlined above.
It has already been suggested, also, to provide, downstream of the couple of rollers a first fulling channel, with a fulling plate, in which the fabric was introduced by the rollers prior to reaching a second fulling channel, and to provide a special thrust member adapted to cause the fabric to be fed forward into the second fulling channel. Also in this case, the thrust into the first fulling channel was produced by the pressure between the two rollers and thus such a pressure had to be, of necessity, very high, whereby the defects outlined above, such as marblings and fabric creases were incurred and the hose form fulling had to be resorted to: in spite of all these precautions, the linear speed of the fabric was unsatisfactorily low.